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A new modeling strategy called F-TACLES (Filtered Tabulated Chemistry for Large Eddy Simulation) is developed to introduce tabulated chemistry methods in Large Eddy Simulation (LES) of turbulent premixed combustion. The objective is to recover the correct laminar flame propagation speed of the filtered flame front when subgrid scale turbulence vanishes as LES should tend toward Direct Numerical Simulation (DNS). The filtered flame structure is mapped using 1-D filtered laminar premixed flames. Closure of the filtered progress variable and the energy balance equations are carefully addressed in a fully compressible formulation. The methodology is first applied to 1-D filtered laminar flames, showing the ability of the model to recover the laminar flame speed and the correct chemical structure when the flame wrinkling is completely resolved. The model is then extended to turbulent combustion regimes by including subgrid scale wrinkling effects in the flame front propagation. Finally, preliminary tests of LES in a 3-D turbulent premixed flame are performed.

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Due to their negative impacts on environment and human health, future regulations on soot emissions are expected to become stricter, in particular by controlling the size of the emitted particles. Therefore, the development of precise and sophisticated models describing the soot production, such as sectional

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A complete numerical coupling between radiation and turbulent convection in a channel gas flow has been performed for different temperature, optical thickness (pressure) and wall emissivity conditions. In this model, radiation is treated from the CK approach and a Monte Carlo transfer method; The flow by a Direct Numerical Simulation. Both the effects of turbulence on radiation fields and of radiation on turbulent fields are accounted for. Gas-gas and gas-wall radiation interactions generate antagonist effects on the temperature and flux fields. The first one tends to increase wall conductive flux while the second one to decrease it. Consequently, the structure of the temperature field and the wall conductive flux often strongly differ from results without radiation. Classical wall log-laws for temperature are then strongly modified by the global radiation effects. Many conditions encountered in applications are discussed in the paper. The observed modifications depend on all the set of conditions (temperature level, wall emissivity, pressure, Reynolds number), i.e. on the relative magnitudes of radiation gas-gas and gas-wall phenomena and of global radiation flux and conductive flux without radiation.